西藏羊卓雍错流域冰川-湖泊动态变化研究

Dynamic variations of glaciers-lake in YamzhoYumco basin of Tibet

基于landsat卫星数据,数字高程模型(DEM)数据以及气象数据,借助遥感和地理信息系统技术,定量分析了1977年到2012年西藏羊卓雍错流域内冰川、湖泊的变化及其原因。结果表明:35年间该流域冰川面积持续缩小,并且在2000年以后有加速退缩的趋势,共减少了58.45km2。湖泊经历了先缩小后增大再加速萎缩的过程,35年来湖泊共缩小了46.19km2。流域35年来年均气温上升明显,尤其是冬季气温上升幅度大,气温的升高是冰川快速退缩的主要原因;湖泊的消涨取决于降水和蒸发的综合作用,冰川和湖泊之间的水文关系不显著。该区域近年来有暖干化的趋势,水资源压力较大。

Based on the Landsat satellite images, digital elevation model（DEM） data and meteorological data, with remote sensing and geographic information system technology, the glacier and lake variations from 1977 to 2012 in the basin as well as the causes were analyzed. Glaciers in the basin shrinked during last 35 years, and the trend of shrink accelerated after 2000. Glacier had decreased by 58.45km2. Lake decreased firstly then ex- panded and decreased quickly at last during this period. Lake in the basin has decreased by 46.19 km2. Air temperatures of the basin rose significantly, especially the winter air temperature. Glacier change was controlled by temperatures rise, but lake fluctuating depended on the combined effects of precipitation and evaporation. The connection between glaciers and lakes of the study area was not obvious. In recent years there was a warm - dry trend in this region, and big water resources pressures existed.